Dan - Thanks, I'll have the battery load tested if I can't find anything else. My battery has been babied, battery tended, and recently charged to be sure it was up for this starter routine, but its a number of years old, and I do know that a load test is the only true way ...

Partial response from MAC's - "We sell about 150 of these starters every year and have very few fitment issues." Kinda ignores the fact that when it's in, it doesn't work.

 

Carl, the mica should be flush on starter commutators (look the red factory service manual, it talks about it). If the wiring is intact and not shorted rebuilding is cheap.
Flathead starters

 

Jonas,

In Carl's other thread I posted a couple of pointers on seating the brushes in the starter....it's not something that you normally have to do with a new starter because it should have been done at the factory. Normally during a rebuild, the technician will wrap the comutator with emory cloth with the abraisve side facing out, then put in the brushes and turn the armature by hand to sand the round shape of comutator into the brushes for good contact.

If you have poor brush contact, it could cause slow cranking and high current draw.

Just a thought.

Dan

 

I just found this while surfing the link in the latest Tips & Tricks post reply: Flathead starters. Photos always help, & there's a good explanation of why you don't undercut mica on starters.....

 

Not sure if I have a long term solution but here is what I did.
1. spent some time getting the shaft aligned....when screwed tight to the sheet metal cover at the bell housing, the starter motor had a distinct slope downward to the rear. Loosened the inner bolt and the strap to the engine block to drop the front end a bit.

2. cranked it and the engine started, but it made a helluva racket as the pinion wasn't disengaging. Wiggled the starter to a position where the pinion released and held it there while a friend tightened the bolts.

3. Now it starts the engine every time, but groans a lot while doing so.

CarlH
1949 F3
1997 F150

 

Well, darn. My babied battery is, in the words of the digital load tester, BAD.
Side note - I called several places to ask if they could load test a 6V battery, and most said "no." I mentioned that the load testers I was familiar with had a 6V scale within the larger 12V scale, but no dice. Kids.
The CarQuest store I went to had a digital tester with no 6/12 switch, but when connected the first thing it asked was "Is this a 6V battery? Pretty cool, ran through several tests, then pronounced mine bad.
When I took the time to look up the receipt, it was 2004. Seems like yesterday!

So, new battery, trickled overnight, now the new Mac's starter will groan through one revolution at a time. 'bout what the old starter did, if not worse. Could mean a couple things- both starters are good, solenoid/wiring's bad, or both starters are bad.

I get a voltage drop from 6.4 to 5.2 between the posts of the battery when trying to crank. That's the posts, not the clamps. I'll continue to check connections, cables, and the solenoid, but I thought that was quite a drop.
Oh, and the properly-sized cables, including a flat braided ground cable, get nice and warm!

Why might a new starter be at the wrong angle, etc, if the old starter once worked fine?

I can't get it started to determine if the bendix releases.

It's all very disappointing. Should have been a simple job.

 

Not sure if we are having the same problem, but I plan to have my original starter motor rebuilt to give more torque. The "new" one from MAC's groans a lot before starting the engine. It just should not act that way!

CarlH
1949 F3

 

I suspect that's your problem (or one of them) right there. First of all, does it connect directly to the block, or to the firewall? It needs to be on clean bare metal on the block.

Second, I don't know how you compare braided cable to conventional, but my experience has been that a large braided cable doesn't carry as much as a proper copper cable. Measure the voltage drop from one end of the cable to the other while cranking. I'd bet it's the braided where you get the biggest drop.

 

Ross -

Thanks for the tips.
I made myself a little chart, and am checking the voltage drops at each potential drop location. Only mV so far.
The ground cable is last on the list!
Too much to do, I only get back to in once in a while.
However, that ground cable has been starting the truck since I bought it in 1997, and probably long before that. It's bolted to the block at one of the bolts holding the coil bracket.
I'm checking everything before I have to fight with that starter to get it back out, then fight with Mac's for a refund.
And now the clutch in the daily driver is going ....
sigh.

Jonas

 

You know, I re-read your earlier post where you said the battery voltage dropped to 5.4. I hate to say it but that sounds like a problem. What is the CCA rating on the battery? A 20% drop in voltage will mean a 20% increase in current for same effort.

 

Ross, did these trucks come with a factory ground cable?

 

Ok, I've used up most of my patience. I'm convinced my wiring is fine, new bat'ry, and that the new starter itself is bad.
Now I can't get it out.
Carl, how did loosening the lower cover help get it out? It seems my conflict is between the ring gear and the bellhousing. I've removed the starter body so I move the armature around to get better angles, but I still can't get the new Bendix started past the ring gear.
I'm in the process of dropping the lower cover completely, which I hope will give me room for a lever (I know if won't come all the way off since its around the starter).
Ross, any more tips on removing the can in the back? I smacked it, not too hard yet, but it doesn't budge. I thought of a dowel sneaked past the starter from the front, but haven't tried it yet. Plus, I'm not sure removing it will help much (I'm on my back on a creeper -where's that lift?).

Any tips would be appreciated.
Jonas

 

If you can drop the cover plate down and outwards on the passenger side, I would think you would be able to get a lot more room, limited only by the bendix hitting the can until you get it out a ways. I wonder if your bendix has come apart?

I'd use the dowel trick to remove the can, but only as a last resort. It has a rolled bead that seats from the inside. At that point you may as well pull the trans back...

 

Thanks. Ross -

No, the Bendix has not come apart. I don't know if you've seen these "modern" Bendix - where the old ones had an exposed spring, the new spring is covered with a metal can of it's own, and that's the problem - the covering is a larger diameter than the old exposed spring, and fits only when forced between the bellhousing and ring gear. You can look at them on the Mac's online catalog. If you've already seen a hundred of them, never mind!

If I drop the cvoer plate I will either be able to get the right angle to get the Bendix cover to start past the ring gear, or get a lever in there to force it past. It went in, I know if will come out, but sheesh - these "new" parts just kill me.

Then I have to discuss it with Mac's ...

I didn't just have my old one rebuilt so I could save time. Right.

Thanks again,
Jonas

 

Well, I got the "new" starter out with a lot of hassle. Got it at an angle, then rotated the engine by hand, which kind of rolled the Bendix cover between the ring gear and the bellhousing, then I could force it out.
No response yet from Mac's re returning it.

I took a closer look at my original, and discovered the wires for one hot brush were shorting against the case. I fixed that, bolted it back in, and of course it works. The new battery and cleaned connections can't hurt!

I took an extra starter motor to Crank-N-Charge, a local place that had rebuilt my generator, and they said they couldn't do the starter! He's checking today about whether he can find parts.

I see I can get brushes, bushings, and a post from our normal sources. Should have just done that in the first place.

Thanks, everyone, and good luck, Carl.

Jonas